Whale warning to jet skis: 'I thought they would get flipped'

Imogen de Vries was watching the pod of about 10 whales during her lunch break from the King Edward Park lookout when she spotted the jet ski carrying two people.

The pair followed the pod all the way from the Bogey Hole to Nobbys beach, often less than 20 metres away from the whales. At one point, the jet ski was in the midst of the pod, surrounded on all sides by the huge mammals.

"It's not just dangerous for the whales. They were on a tiny jet ski in the middle of a big pod, who were clearly thrashing about hunting something," Ms de Vries said.

"I honestly thought they would get flipped."

Jet skis and other personal watercraft must keep a minimum distance of 300 metres from whales, because they create less noise underwater than other vessels and are capable of fast or erratic movements.

"This means personal watercraft are more likely to collide with a marine mammal," a Transport for NSW spokesperson said.

The Newcastle Herald understands NSW Maritime Police were informed of the incident.

Ms de Vries said the whales were splashing around and charging the surface, and appeared to be hunting.

"I go watch the whales all the time, and they're normally pretty chill, but these ones were really hunting," she said.

"They looked smaller than the humpbacks. It was hard to see clearly but I thought they could have been really big dolphins or potentially orcas."

Other water vessels, including boats, must keep 100 metres away from pods and 300 metres away if there is a calf.

Winter marks the peak of the whale migration season, as thousands take the humpback highway north along the east coast of Australia in search of warmer waters.